Picture reception systems such as TV and VCR, in general, have a device for automatic channel memory or manual channel memory.
The device for automatic channel memory searches all channels and memorize those channel numbers which have an input of a broadcasting signal, ie., when a user presses the automatic channel memory key, the channel numbers goes up and down automatically picking up only those channels which had been memorized in the device to memorize those signals having a broad casting signal.
However, when used while watching the television, such a device for automatic channel memory puts, being synchronized with those channels one by one not only those channels having a broadcasting signal, but also even those channels having no broadcasting signal, on the frames.
By the consequence, there has been problem in the automatic memory of channels because even those noise pictures and noise voices from those channels having no broadcasting signal happen to come on interfering watching of the television.
On the other hand, the device for manual channel memory memorizes or erases channel numbers into/from the memory by manual operation of an add key or an erase key after selection of a channel by pressing a channel control key.
However, the trend of current development puts its emphasis on the device for automatic channel memory rather than on the device for manual channel memory because of the inconvenience of pressing of the keys of the device for manual channel memory.